Frequently passageway or pipe carrier surfaces become or are unsuitable for their intended purpose. For example, a newly formed pipe length for carrying fluid or other medium may have a small fracture or hole, or the inner surface may be imperfectly formed so as to be unsuitable for the intended purpose or in the case of an existing pipe length, the inner surface may have become unsuitable simply as a result of wear and tear through usage. Again, with underground passages, such as sewers and mine shafts, the walls defining such passages may deteriorate as a result of use, so that such surfaces allow the undersirable leakage therethrough into the passage of fluid such as water from the outside of the passage, or the leakage therethrough from the inside of the passage of the fluid being carried by the passage. Also, in the case where an underground passage carries a fluid medium such as sewage, erosion of the surface defining the passage by the flow of the fluid and solid matter therein can make the surface rough and irregular, causing difficulties with the flow of the fluid.
When such a difficulty has arisen in the past, the only course considered available before the present invention, was the replacement of the pipe length or whole pipe in the case of pipelines, or the formation of a new underground passage, in the case of an underground passage.